Chunking a django-import-export

Chunking in Django-import-export refers to the process of importing or exporting data in smaller batches or chunks, rather than processing the entire dataset in a single operation. Chunking can help manage memory usage and prevent timeouts when dealing with large datasets.

By default, Django-import-export does not provide built-in support for chunking. However, you can implement chunking yourself using Django's queryset slicing and importing/exporting data in smaller portions.

Here's an example of how to chunk an import using Django-import-export:

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# Assuming you have a Django model called YourModel and an associated resource class YourModelResource for import/export

from import_export.resources import ModelResource
from import_export.fields import Field

class YourModelResource(ModelResource):
    # Define your fields and other configurations here

def chunked_import(data, resource_class, chunk_size=1000):
    start_row = 0
    while start_row < len(data):
        end_row = start_row + chunk_size
        dataset = data[start_row:end_row]
        resource = resource_class()
        result = resource.import_data(dataset)
        if not result.has_errors():
            # Handle successful import (optional)
            pass
        else:
            # Handle import errors (optional)
            pass

        start_row = end_row

# Usage example
# data is a list containing the data to import
# resource_class is your resource class for YourModel
chunked_import(data, YourModelResource)

In this example, we define a function chunked_import that takes the data (a list) to import, the resource class, and an optional chunk_size parameter (defaulting to 1000).

The function then iteratively imports the data in chunks using slicing. It creates a new resource for each chunk and imports the data using import_data(dataset).

You can apply a similar approach to chunk the data during exporting as well. The concept is the same, but you will need to implement the slicing for exporting and handle any additional processing or saving logic as needed.

Keep in mind that when chunking, you need to be cautious about handling unique constraints and avoiding duplicate data entries. Additionally, make sure to handle any potential side effects or dependencies between the data chunks during import/export.